Document WO 97/27102 describes a method and apparatus for removing a propeller assembly from an opening of a swimming vessel, wherein the propeller assembly is designed to close an opening in the vessel hull when the propeller assembly is in its mounted position. According to this prior art, a watertight hoisting chamber is provided around the propeller assembly and inside that hoisting chamber a drive shaft is provided, which leads to a drive motor positioned in the vessel and outside of the hoisting chamber. When the known propeller assembly is to be removed, the drive shaft is removed first, then its passage through the hoisting chamber wall is closed in a watertight manner, after that the propeller assembly is connected to hoisting means and then a flange of the propeller assembly is loosened. Then, the propeller assembly can be lifted from the hoisting chamber. The propeller assembly is also known as thruster.
The method according to the prior art requires assembly/disassembly work which has to be carried out under water.